The Change event symbol is used to signal another part that the attribute value has changed.

If you select the Add with defaults or Defaults push button, the change event symbol name is the same as the attribute name. For example, if the attribute name is order Changed, then the change event symbol is also order Changed.

The field includes a drop-down list. You can assign any of the items as the Change event symbol.

You do not have to specify a value in the Change event symbol field. If you do not specify a name, other parts will not know when an attribute is updated and consequently might have an old value for that attribute. For example, if an entry field is connected to a street attribute and the street is updated by the database, the entry field will not be notified of the update so will contain an old address.

If you generate a set selector for your attribute, the change event is signaled in the default code generated by VA Smalltalk.